Materials - Modern

Alec Stevens
Flashcards by , created almost 6 years ago

A-Levels Resistant Materials (Materials) Flashcards on Materials - Modern, created by Alec Stevens on 05/04/2013.

Eye 75
Pin 2
Balloon left 0
Tags
Alec Stevens
Created by Alec Stevens almost 6 years ago
Resistant Materials
Elisha
GCSE Revision (Plastics detailed) AQA specification
T Andrews
Materials and their properties (updated Oct)
T Andrews
Exchange surfaces and breathing
megan.radcliffe16
Study tips/hacks
Sarah Nadia Biswas
Chemistry Module C2: Material Choices
James McConnell
GCSE revision (Sustainability)
T Andrews
Resistant Materials- 1.1 Material properties
fampulli
Materials
Billie Juniper
Plastics
fampulli
Question Answer
Thermo-Ceramics Very advanced ceramic materials, a combination of ceramic and metallic powders through sintering (mixed, heated and then subjected to very high pressure till particles bond). Internal structure which makes them extremely HARD and STABLE AT VERY HIGH TEMPERATURES. Can be brittle, if imperfections it can crack. Significantly more expensive than traditional materials. Used in turbo chargers of racing cars/turbine blades in jet engines.
Tinted and Photochromic Glass Photochromic glass auto-darkens when exposed to UV, then revert to clear. The glass is impregnated with silver halide particles. Process reversible because particles are encapsulated and sealed within glass. Used in spectacles which auto darken outside.
Solar Panels (PV/Photovoltaic) Thin layers of silicon with various impurities added. When exposed to sunlight, one layer rich in electrons, one layer deficient - so there is a p.d. between the layers. Power limited so large number of cells needed to produce a good effect. Renewable, possible alternative to fossil fuels, expensive to produce and normally used in places where mains power is not readily available.
Liquid Crystal Displays (LCD) Organic, carbon based compounds which exhibit both liquid and solid characteristics. When a cell containing liquid crystal has a voltage applied, it appears to go dark because of molecular rearrangement. Very small amounts of current required so more sustainable. Also good to use in applications where battery life/size is limited like mobile phones.
Electroluminescent Lighting (EL lighting) Converts electrical energy into light by applying voltage across electrodes with an organic phosphor between them. This charges the phosphor crystals which emit light. Very low power consumption so good for use as a backlight or use in advertising to produce posters with a high visual impact. Lighting is produced in form of paper thin wires or panels. LIMITED LIFE SPAN OF ORGANIC PHOSPHORS.